[FFmpeg-cvslog] Fixed invalid read access on extra data in cinepak decoder.

[Laurent Aimar]

ffmpeg | branch: release/0.8 | Laurent Aimar <fenrir at videolan.org> | Sun Sep 11 19:17:43 2011 +0200| [c9316b7c6d30e87f469ca6d9651f26eff5f4c6e9] | committer: Michael Niedermayer

Fixed invalid read access on extra data in cinepak decoder.

Signed-off-by: Michael Niedermayer <michaelni at gmx.at>
(cherry picked from commit dc255275f6293a060518271a151e1ce75499e874)

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=c9316b7c6d30e87f469ca6d9651f26eff5f4c6e9
---

 libavcodec/cinepak.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/libavcodec/cinepak.c b/libavcodec/cinepak.c
index 57657af..0b822d2 100644
--- a/libavcodec/cinepak.c
+++ b/libavcodec/cinepak.c
@@ -336,7 +336,8 @@ static int cinepak_decode (CinepakContext *s)
              * If the frame header is followed by the bytes FE 00 00 06 00 00 then
              * this is probably one of the two known files that have 6 extra bytes
              * after the frame header. Else, assume 2 extra bytes. */
-            if ((s->data[10] == 0xFE) &&
+            if (s->size >= 16 &&
+                (s->data[10] == 0xFE) &&
                 (s->data[11] == 0x00) &&
                 (s->data[12] == 0x00) &&
                 (s->data[13] == 0x06) &&